envz_add - Online Linux Manual PageSection : 3
Updated : 2023-02-05
Source : Linux man-pages 6.03
NAMEenvz_add, envz_entry, envz_get, envz_merge, envz_remove, envz_strip − environment string support
LIBRARYStandard C library (libc, −lc)
SYNOPSIS#include <envz.h>error_t envz_add(char **restrict envz, size_t *restrict envz_len,
const char *restrict name, const char *restrict value);char *envz_entry(const char *restrict envz, size_t envz_len,
const char *restrict name);char *envz_get(const char *restrict envz, size_t envz_len,
const char *restrict name);error_t envz_merge(char **restrict envz, size_t *restrict envz_len,
const char *restrict envz2, size_t envz2_len,
int override);void envz_remove(char **restrict envz, size_t *restrict envz_len,
const char *restrict name);void envz_strip(char **restrict envz, size_t *restrict envz_len);
DESCRIPTIONThese functions are glibc-specific. An argz vector is a pointer to a character buffer together with a length, see argz_add(3). An envz vector is a special argz vector, namely one where the strings have the form "name=value". Everything after the first '=' is considered to be the value. If there is no '=', the value is taken to be NULL. (While the value in case of a trailing '=' is the empty string "".) These functions are for handling envz vectors. envz_add() adds the string name = value (in case value is non-NULL) or name (in case value is NULL) to the envz vector (*envz, *envz_len) and updates *envz and *envz_len. If an entry with the same name existed, it is removed. envz_entry() looks for name in the envz vector (envz, envz_len) and returns the entry if found, or NULL if not. envz_get() looks for name in the envz vector (envz, envz_len) and returns the value if found, or NULL if not. (Note that the value can also be NULL, namely when there is an entry for name without '=' sign.) envz_merge() adds each entry in envz2 to *envz, as if with envz_add(). If override is true, then values in envz2 will supersede those with the same name in *envz, otherwise not. envz_remove() removes the entry for name from (*envz, *envz_len) if there was one. envz_strip() removes all entries with value NULL.
RETURN VALUEAll envz functions that do memory allocation have a return type of error_t (an integer type), and return 0 for success, and ENOMEM if an allocation error occurs.
ATTRIBUTESFor an explanation of the terms used in this section, see attributes(7). InterfaceAttributeValue envz_add(), envz_entry(), envz_get(), envz_merge(), envz_remove(), envz_strip() Thread safetyMT-Safe
STANDARDSThese functions are a GNU extension.
EXAMPLES #include <envz.h>
#include <stdio.h>
#include <stdlib.h>
int
main(int argc, char *argv[], char *envp[])
{
char *str;
size_t e_len = 0;
for (size_t i = 0; envp[i] != NULL; i++)
e_len += strlen(envp[i]) + 1;
str = envz_entry(*envp, e_len, "HOME");
printf("%s\n", str);
str = envz_get(*envp, e_len, "HOME");
printf("%s\n", str);
exit(EXIT_SUCCESS);
}
SEE ALSOargz_add(3) 0
Johanes Gumabo
Data Size : 13,823 byte
man-envz_entry.3Build : 2024-12-05, 20:55 :
Visitor Screen : x
Visitor Counter ( page / site ) : 2 / 185,378
Visitor ID : :
Visitor IP : 13.58.245.158 :
Visitor Provider : AMAZON-02 :
Provider Position ( lat x lon ) : 39.962500 x -83.006100 : x
Provider Accuracy Radius ( km ) : 1000 :
Provider City : Columbus :
Provider Province : Ohio , : ,
Provider Country : United States :
Provider Continent : North America :
Visitor Recorder : Version :
Visitor Recorder : Library :
Online Linux Manual Page : Version : Online Linux Manual Page - Fedora.40 - march=x86-64 - mtune=generic - 24.12.05
Online Linux Manual Page : Library : lib_c - 24.10.03 - march=x86-64 - mtune=generic - Fedora.40
Online Linux Manual Page : Library : lib_m - 24.10.03 - march=x86-64 - mtune=generic - Fedora.40
Data Base : Version : Online Linux Manual Page Database - 24.04.13 - march=x86-64 - mtune=generic - fedora-38
Data Base : Library : lib_c - 23.02.07 - march=x86-64 - mtune=generic - fedora.36
Very long time ago, I have the best tutor, Wenzel Svojanovsky . If someone knows the email address of Wenzel Svojanovsky , please send an email to johanes_gumabo@yahoo.co.id .
If error, please print screen and send to johanes_gumabo@yahoo.co.id
Under development. Support me via PayPal.