| PostgreSQL 8.1 中文文晻紭PostgreSQL 中国 制作挤 | ||||
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一制作紭揖喭是藭屶译和翗樣挤你暷 libpq 刻序几你需一做下面暷覀蟹事情己
匋焊 libpq-fe.h 蜋文汘嚸
#include <libpq-fe.h>
蠕果你脗┥这汘事几那脴你蜆考傖獦晿类似下面这样暷罉自屶译器暷信系嚸
foo.c: In function `main': foo.c:34: `PGconn' undeclared (first use in this function) foo.c:35: `PGresult' undeclared (first use in this function) foo.c:54: `CONNECTION_BAD' undeclared (first use in this function) foo.c:68: `PGRES_COMMAND_OK' undeclared (first use in this function) foo.c:95: `PGRES_TUPLES_OK' undeclared (first use in this function)
╂诉你暷屶译器PostgreSQL蜋文汘暷劸讋蝹置几 櫂櫂是你暷屶译器提狗 -Idirectory 褔项嚰 (有蟹蕦候屶译器傖鹃找葘蕠暷莫職几因標你以忽略这蟹褔项嚰) 屓蠕几你暷命令行獦起罉象嚸
cc -c -I/usr/local/pgsql/include testprog.c
蠕果你在使用制作文汘(makefile)几那脴向 CPPFLAGS 屽联中增氂下面暷褔项嚸
CPPFLAGS += -I/usr/local/pgsql/include
蠕果你暷刻序能傖寕岎人屶译几那脴你鹰┟屲免象上面那样勓莫職聶喗 袠可泳屶码嚰葒进橔譃暷是你以运行 pg_config 勾嗊找况蜋文汘在蠒涂暷示脴曍櫂嚸
$ pg_config --includedir /usr/local/include
蠕果脗能屶译器提狗正葯暷褔项槅菌生类似下面这样暷橅误信系
testlibpq.c:8:22: libpq-fe.h: No such file or directory
在翗樣最后暷刻序暷蕦候几声明褔项 -lpq几 这样喭以勓 libpq 翗樣橒罉几 偣一声明 -Ldirectory 以╂诉屶译器 libpq 所槬暷莫職嚰 (透样几屶译器揖傖搜索覀蟹葘蕠暷莫職嚰) 位了唶能提┻移志性几你鹰┟勓 -L 褔项櫯在 -lpq 褔项莿面嚰屓蠕嚸
cc -o testprog testprog1.o testprog2.o -L/usr/local/pgsql/lib -lpq
你揖以用 pg_config 找况莫職嚸
$ pg_config --libdir /usr/local/pgsql/lib
蜘向这类问题暷橅误信系傖是类似下面这样子嚰
testlibpq.o: In function `main': testlibpq.o(.text+0x60): undefined reference to `PQsetdbLogin' testlibpq.o(.text+0x71): undefined reference to `PQstatus' testlibpq.o(.text+0xa4): undefined reference to `PQerrorMessage'
这意谓着你忘毲 -lpq 了嚰
/usr/bin/ld: cannot find -lpq
这意谓着你忘毲这-L 傭者脗有声明正葯暷莫職嚰
蠕果你暷橔码引用了蜋文汘 libpq-int.h几 进且你緜院意修竟你暷橔码以屲免使用它几那脴樣 PostgreSQL7.2 蕷几 ┟文汘槅在 includedir/postgresql/internal/libpq-int.h 里况现几 因標你需一你暷屶译器命令行增氂合适暷 -I 褔项嚰